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Atx power supply problem pleas help. Answered

I am wanting to turn atx psu into power supply, connected up to check. all wiring is correct added a 10 ohm 5 watt load resistor standby comes on connect green and ground to switch on. fan starts to spin then stops , any ideas anyone


Jack A Lopez

23 days ago

I dunno. I think I would try it without the load resistor connected.

I mean, try connecting a load after you have coaxed the thing into turning itself on.

This Wikipedia article has some words about pinouts of teh ATX power connector,

Pin 16: Power on. (Green wire.) [Note E] A control signal that is pulled up to +5 V by the PSU and must be driven low to turn on the PSU.

and that is kind of what we were expecting. Amirite? Connect green wire to ground, and it gets pulled low, signals PSU to turn on. Disconnect green wire from ground, and PSU pulls it high, and this signals PSU to turn off.


23 days ago

Lots of ideas actually...
Thes mods are for old PSU's, new model often have added checks on other voltage rails.
Plus the green wire needs to stay connected for as long as you need power.
The 10 Ohm resistor might not be enough, if no hassle then just try one or two break lights from a car or a 12V halogen light bulb on the 5V rail.